


Hybridized Heat

by Qmii_Productions



Series: Animal Hybrid AU [1]
Category: OMORI (Video Game)
Genre: Alternate Universe - Animals, Amazonian Press, Animal Genitalia, Animal Instincts, Cat/Human Hybrids, Creampie, Dog/Human Hybrids, F/M, Femdom, Fingering, First Time, Fluff, Fluff and Smut, Heat/Mating Cycles, Hybrids, Interspecies Sex, Knotting, Masturbation, Mating Press, Multiple Orgasms, Nipple Play, No death AU, Oral Sex, Orgasm Denial, Porn With Plot, Reverse Mating Press, Riding, Table Sex, Tail Sex, Vaginal Sex, imagine my surprise finding out that position had a name
Language: English
Status: In-Progress
Published: 2021-02-12
Updated: 2021-02-12
Packaged: 2021-03-12 17:01:57
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 3,246
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/29388123
Author URL: https://archiveofourown.org/users/Qmii_Productions/pseuds/Qmii_Productions
Summary: Unlike normal cats, the estruses of human-cat hybrids didn’t start with puberty. Rather, it always began at 18 years or older. Mari finally reached her estrus cycle, and she’s in need for some help.—A Heromari lemon, taking place in an animal hybrid au.
Relationships: Hero/Mari (OMORI)
Series: Animal Hybrid AU [1]
Series URL: https://archiveofourown.org/series/2185113
Comments: 12
Kudos: 23





	Hybridized Heat

**Author's Note:**

> This takes place in a timeline where *that* never happened. So Mari grows up with Sunny for 4 years. However, Aubrey still grows to be a hooligan through some misadventures. Fortunately, she still acts like her younger self when the right circumstances arise.

**Summary for the Chapter:**

> How does a catgirl mastubate? The answer surprises Hero.

**Notes for the Chapter:**

> Here are the definitions of some unfamiliar terms:  
>  **Pars longa glandis** \- the area between the bulb and tip  
>  **Prepuce** \- the opening of the sheath

“Hey, Sunny.” Kel asked.

“Yeah?”

“Is it just me, or is your sister being a lot more  physical with Hero today?”

The titular six friends were currently at the treehouse. It was another one of their summer sleepovers. Sunny was clambering on the branches around the tiny playhouse, while Kel talked to his friend from the window. The dog hybrid’s claws were too blunt to catch up with the agile catboy. Mari, Hero, Aubrey, and Basil were currently playing some game on their Switches, with the older cat/dog pair having lost already.

“Yup, I’ve noticed.” Sunny began testing his weight on the thinner branches. Like all humanoid hybrids, his legs were structured like his nonhuman counterpart; though his thighs and calves were human, his feet were digitigrade. They had raised heels and completely feline paws. Sunny protracted the claws on these paws, digging them into the thin bark. He crouched, placing his hands between his feet, tail hanging below him like a black hairy snake. “I would tell you why, but it’s a little... well...  private.”

To put it simply, Mari went into her first heat. Unlike in normal cats, the estrus cycle of human-cat hybrids didn’t always start at puberty. The heat could begin at different times after that, depending on the individual. For Mari, she only had to deal with menstruation at 11 years old. That was until two days ago, when she began growing more restless. Her fluffy plumed tail always seemed to be kept tucked between her legs. She rubbed her purple-dyed hair and ebony ears over seemingly everything that was hers - the piano, the bed, and even her own brother. Because of this, their mother warned Sunny to keep his distance from his sister - she was likely very uncomfortable in this new phase of her life.

Sensing that he was treading on a sensitive topic, Kel turned his attention towards the couple in question. With all of the friends having super-sensitive hearing, hopefully they ignored Sunny’s implication for their game of Last Card. The pink-haired lop rabbitgirl was busy with in an intense final round with the blonde roe deerboy. Meanwhile, Mari was getting a little more flirtatious than usual, her tail coiling around Hero’s back and his curled Akita-like tail. She was purring up a storm and spreading her scent on her mate’s neck and chest. So much so that Kel inwardly retched before turning back to continue talking to Sunny.

“Hmmm... Hero, you smell really good today...” the catgirl purred into his shoulder. “It’s a little... musky. I love it.”

“Uh... thanks?” Hero replied, perplexed. His sensitive nose also detected an interesting scent from his girlfriend. A fruity-fishy smell, but it was a little muted.

“Hey, Henry. I’ve got an idea for you...” Mari grinned smugly. She brought her lips as close as she could to her boyfriend’s right semi-erect ear flap.

“Meet me at the treehouse tonight at 12.” Hero’s tail started wagging with excitement, despite his human brain not getting the clue.

“AW, COME ON!” An exasperated Aubrey yelled, slamming her Switch down.

“Heh... sorry, Aubrey. Better luck next time.” Basil said sheepishly.

“THAT’S THE THIRD GAME IN A ROW YOU’VE SAID THAT!”

* * *

It was a good thing that the living room was carpeted, because one of the disadvantages to having canine feet was creating a clacking noise whenever their claws hit tile or wood. And Hero didn’t clip his toe claws this week. Regardless, he managed to sneak outside with everyone else still asleep. It must have been a miracle, since he knew that Basil and Aubrey - as part prey-animals - had the most acute hearing out of the group.

“Ah-“  ***squish*** “Ah-“  ***squish***

Speaking of hearing, immediately after shutting the patio door, Hero’s left ear turned towards a strange sound. It was faint, and the partial floppiness of his ears somewhat impaired him, but he could still hear it. It sounded wet, like stepping in a thin puddle on a rainy day. Along with the splashing sound, he heard an exhale - a breathy one. The fishy-fruity smell also returned, but it was stronger - as if a scented candle was just opened. Hero’s curiosity guided him towards the source.

His digitigrade legs led him back to the treehouse, with a dim light coming out of its window. The squishy noises grew louder, but not as loud as the moans that accompanied them. He never heard these kinds of sounds from Mari before.

“Mari? Are you ok?” Hero called from below.

Mari didn’t respond, continuing to moan louder. “Gyah-“  ***squish*** “Ah-“  ***squelch*** “AH-“

The strange smell also intensified as he went closer to the ladder. Correlating the smell with the sounds, Hero’s mind began to draw the conclusion, his face starting to flush. He could feel his canine sheath retract its tip in his briefs as he climbed the ladder. Although he was correct in his assumption, he was still not prepared for what he saw once his head reached the door hole.

The first thing Hero saw was his girlfriend’s panties, drenched with a liquid emitting that peculiar odor. They were on top of Mari’s pajamas. But his attention towards the discarded garments was short-lived, as his eyes immediately darted and widened at the source of the sounds. Hero was pretty certain it was the hottest thing he’d ever seen in his life, period. A buck-naked Mari was lying back on the table, her legs spread apart, with her feet claws creating long scratches on the floor from desperate attempts to stay steady. Her arms went from outstretched across the table to propping Mari’s torso up with their elbows, while her finger claws dug into the wood of the furniture. The most distinctive feature of this scene was Mari’s tail. It was curled inward, its tip thrusting in and out of her exposed vulva at a brisk pace. It was sopping-wet, with drops of clear-to-translucent-white cum dripping around it and onto the wood. Her tail was soaked with the same liquid - if it weren’t for its white tip, it would be pretty blatant that she was using it as a makeshift dildo.

“AH-“  ***SQUISH*** “HAH-“  ***SQUISH*** “HAH-“  ***SQUISH*** “HAH-“  ***SQUISH***

Mari’s tail increased its pace, her flushed sweaty face reeling back with pleasure. With every thrust, her plump C-cup breasts jiggled slightly, their erect pink nipples creating tiny circles. As she approached her climax, Hero felt his blood rushing not only to his face (which was redder then the finest wine), but also to his dick. Its sheath gradually peeled back, revealing more of Hero’s red rocket to his underwear. Mari inserted as much of her tail as she could, its white tip completely disappearing into her hungry snatch.

“NYAAAAAAAAAAAAA!”

By the time Mari’s pussy (pun intended) squirted out jets of cum around her fifth appendage, Hero’s dick was completely freed from its furry prison of skin. His girlfriend panted as the white nether torrents began to slow to quiet trickles, before pulling out her abused tail and letting it lay limp on the scarred, puddle-covered floor. She raised her head towards Hero, her pupils blowing out wide at the sight of her audience. The horny catgirl shut her mouth and wiped a line of drool from it with her left wrist, an evil grin creeping across her face.

“Herooo~” Mari mewled. “In case you haven’t noticed, I believe I’m ready for my first time. Are you?”

“Y-Y-YES!” The aroused dogboy replied louder than he expected. He scrambled to enter the treehouse, resorting to crawling on his own arms, pulling the rest of his torso up. As he was rising to his feet, Mari side-eyed the bulge in his pants and pounced.

Hero ended up taking Mari’s place on the table. As she nearly tore off his shirt and pushed him onto to his back, he could smell faint remnants of cum on her fingers. She was fingering herself before resorting to her tail for self-pleasure. Before the dog hybrid could ask what she was doing, Mari tugged down the waistbands of his pajama pants and boxer briefs in one fell swoop. Hero sharply inhaled with the exposure of his blazing rod to the lukewarm summer air. It was now the dogboy’s turn to look up on his elbows, with Mari parting his legs to examine her prize. His girlfriend crouched between his thighs, licking her lips at the sight of his 7-inch canine cock. It was a dark ruby-red, the pars longa glandis widening to 1-and-a-half-inch diameter, before tapering to a spade-shaped tip. It had no bulging veins, rather being smooth and shiny, interspersed with a network of faint capillaries. A tiny urethra at the tip of that head began to leak clear pre-cum, which Mari caught with a single touch of her tongue.

The catgirl’s lips pursed around her tongue, leaving her kissing the tip of her boyfriend’s dick. Then those lips began to open, engulfing the red rocket’s “cone” into the wet, warm cavern that was Mari’s mouth. Hero released a high-pitched whine, creating small gusts with his wagging tail when she began swirling her tongue around the tip. (Cat-human hybrids thankfully didn’t have their counterpart’s sharp papillae, which would’ve made for a vastly different - and eventually painful - experience.) This encouraged Mari to suck further, hollowing out her cheeks with an exhale through her nose. Eventually her lips reached his knot, the catgirl licking the smooth length from all sides. Those popsicles from the beach certainly helped her practice. Meanwhile, her tail resumed abusing her womanhood again, this time only brushing her vulva and rubbing her hardened clitoris.

Hero’s heavy panting grew more ragged with all this searing pleasure. He had fantasized about this in his wet dreams, after which Kel would tease him for his morning wood. He would then jerk himself off to the thought of knotting Mari. The fact that such a fantasy was now a prospect compounded his bliss. His girlfriend hummed as her head bobbed up and down his length, causing Hero to instinctively grab onto her soft, velvety ears. The canine half of his mind wanted to pound her face, but the human half didn’t want to hurt her. He settled for rubbing, an action that he knew made any cat hybrid purr.

“Mari... I’m gonna-“

She wrestled herself away from his grip, despite the pleasurable stroking she received from him. Hero complained with a sad whine and the signature puppy-dog eyes.

“Sorry, Henry, but I just love it when you’re flustered.” Mari began straddling her boyfriend, making him lay on his back again. Her legs went over his, making him grip her hips with his ankles. She used her tail to push the aching member towards her womanhood. Unlike males, female hybrids rarely had external animal genitals, looking identical to those of a human, albeit furrier. Mari’s hands anchored themselves on Hero’s stomach, and with a single line of praise…

“Good boy.”

…she slowly sank onto his raging red rocket.

Fortunately for the both of them, Mari was born with little to no hymen. There was no blood to stain the wood of the table or floor - a harder clue to erase than cum. The catgirl only sank to the top of his penis’ bulb, much to its owner’s frustration. Hero gripped her ass, trying to push her down further. However, his girlfriend’s pelvis wouldn’t budge.

“Ah-ah-ah,” Mari teased. Even with her mind addled with hormones and instincts, she knew how to push her boyfriend’s buttons. “I’ll get to that part. Just sit back and enjoy the ride.”

And what a ride it was. Every piece of music in the world wouldn’t compare to the sounds that came out of Mari’s panting mouth. With the dim lighting from a simple lantern (there wasn’t one built into the treehouse) and the waning moon, the catgirl looked like an angel. Her purple hair seemed to shimmer, her breasts bouncing with every downward thrust. Mari’s hot pink pussy was as tight as a vice, its muscles constricting around his dick like a boa. The abundance of cum allowed her to slide in and out like melting butter.

“Hah-“  ***PLAP*** “Hah-“ ***PLAP*** “Hah-“ ***PLAP***

Mari had her own fantasies of this moment, of Hero taking her virginity. The dreams grew more frequent and detailed over the days of her heat. It quickly escalated from desiring gentle sex to dreaming of her Hero’s cock piercing and pounding her to oblivion. She was internally glad she got more than she expected, not only getting a great first time, but from a dominant position. Hero’s face was also red, sweaty, and panting, his eyes gaining hearts for pupils. Out of all the expressions she’s seen him make, this one was Mari’s new favorite.

His member stretched her vagina much more than her soft tail, its rigidness allowing Mari to milk her lover for his precum. Even though she didn’t take in the knot, the pars longa glandis was still long enough to reach her cervix. But only ever-so-lightly. Hero thrusted too, brushing the entrance to her womb every time he raised his hips. Mari tried to experiment with a slightly-backwards tilt of her hips. This caused the tip to poke her in the G-spot, causing a spark of electricity to run through her.

“HNYAAAAAAH!”

“AH!” Hero exclaimed. “M-Mari! Your claws!”

The catgirl snapped out of her short ecstasy when she looked down at her hands. Their white thornlike claws were digging into Hero’s stomach, almost breaking the soft skin. Mari quickly withdrew her hands and retracted her claws.

“Oh! Sorry.” She leaned forward, placed her hands next to Hero’s head. Her womanhood pulling Hero’s cock along, so that it was at an acute angle with his torso. Mari cushioned her breasts onto his chest, humming as she felt her nipples harden from the warm skin-to-skin contact. “How’s this?”

“Perfect,” Hero replied. This position allowed him to get a closer look at that beautiful face. His girlfriend’s pupils were blown open with excitement, dark with desire. As she continued riding him, Hero brought his hands to her flushed face, pulling her in for their first kiss of the night. Mari immediately began licking his lips, ravenous for more intimate contact. Hero complied, taking out his tongue to meet hers. They had tried French kissing before, but they silently agreed that it was much better when they were free to touch each other’s bodies without hesitation.

Mari thrusted in a way that Hero’s tip rubbed her G-spot. Although she couldn’t jab herself on his dick again from this angle, she could at least feel continuous sparks traveling up from her core. Her mouth traveled to his neck, licking and suckling its tender skin. Hero got an idea once she reached a brisk thrusting pace.

“Hero...ah…I’m close!”

At her plea, the dogboy gave a small smirk, reaching his right hand over Mari’s back. He used his blunt claws to scratch the base of her tail. During their cuddling sessions, she always went to putty whenever that area was touched. This time, it sent the catgirl over the edge.

“N-NYAAAAAAAAAAAH!” Mari yowled from her second orgasm, pushing herself onto Hero’s knot so hard that it finally slipped inside.

** *POP***

“HHNG!” Hero grunted, feeling his dick shoot its load. He held Mari down onto his pelvis, their hips finally meeting together. The catgirl didn’t resist, her mind too swamped with ecstasy to pull out. His bulbis glandis was quite neglected during this session, only being warmed by the trickles of cum dripping down from his lover’s vulva. Both Mari and Hero moaned as the knot expanded from the sudden hot embrace. The former felt satisfied from having her cervix jabbed with the inclusion of the knot, while the latter reveled in the fact that he was now tied with his chosen mate.

“Hah...hah...hah... Thank you...Hero...” Mari panted.

“No...hoooh...problem.” Hero replied.

They stayed like this for a few seconds.

“Dammit...I’m still...horny...” The catgirl breathed in frustration. “C’mon Henry, we’re going again-“ She began rising from the dogboy’s hips.

“YIPE!” Hero yelped. It felt like she wanted to rip his dick off. Mari paused and sat up, seeing a slender red rod of flesh tethering their crotches together.

“C-careful! We’re gonna be like this for a while.” The dogboy warned. “And I don’t think I have the energy for another round.”

_Curse your below-average stamina._ Mari’s cat instincts complained.

“I thought knots only lasted a few seconds,” Mari said.

“Did you get that from porn?” Hero asked. When it came to sexual education, animal hybrids were taught about the reproduction of their corresponding species.

“...Maybe.” She admitted. “But I still feel so hot! Could you please touch me?”

“Let’s get off this table first.” Hero replied.

To the dogboy’s fortune, Mari had brought a queen-sized futon from her basement. Although the tie impaired their progress, they managed to get the bedspread open and lie down on it, Hero still below her.

Hero brought his mouth over Mari’s left nipple, his hands groping the lovely pillows of flesh. The catgirl purred in contentment; she didn’t have the biggest breasts, but they were perfect to the dog hybrid. The suckling activated the cat hybrid’s maternal instincts, her mind bringing images of offspring taking their first meal. In the back of her mind, she knew such a future would be impossible. But just for this moment, she wanted to dream.

The suction and tweaking of her nipples brought more electricity to her clit. When Hero switched nipples, he brought his right hand to thumb Mari’s clit, and snaked his left hand to scratch the base of her tail again. All three stimuli sent her grinding on her boyfriend’s balls, until she was cumming around them again.

“MYAAAAAH~” Hero was pretty certain her cries were his new favorite sounds. This seemed to wear out the cat side of Mari, making her collapse on top of him. She was grinding so long that Hero’s knot deflated and shrunk, exposing the catgirl’s stuffed womanhood. He pulled up the covers, satisfied.

Looking in the window, he noticed that there was a digital clock with an activated alarm. She must have brought it there to clean up later. With a wide yawn, Hero fell asleep, catgirl in his arms. He may not have expected this for their first time, but he was far from disappointed.

* * *

“Alright, guys! Who’s up for some Smash Bros?” Kel exclaimed.

“Hey, guys!” Mari called out from the window. She and Hero had woken up early, making sure not to wake the others as they cleaned up. His dick had already retracted, and Mari’s womanhood hidden by a new pair of panties.

“Mari? When did you get here?” Basil asked.

“She helped me set up the TV,” Hero replied beside her. “We found a portable generator in the basement.”

As the rest of the teens made it to the treehouse, Mari looked towards Hero with familiar eyes. Eyes darkened with longing and lust. The dog hybrid silently gulped, feeling his prepuce retract again...

“Hey, why does the table smell weird today?” Kel asked.

Sunny, suspicious of Hero’s widened eyes, his sister’s smug expression, and both of their reddening faces, made a mental note to talk to the older dog hybrid in private later. His mom told him that a cat’s heat can last 6 days at least. Hopefully Hero could improve his stamina from this.

**Notes for the Chapter:**

> Why did I do this? Because there’s hardly any Heromari smut. I have a second chapter in mind.
> 
> I learned some really interesting facts about the dog penis while writing this. For instance, did you know their dicks can be purple? I think I met a few dogs like that. It's strange how I can visualize that and not deem it as fiction.
> 
> BTW, Basil and Aubrey were playing Clubhouse Games for the Switch.

**Author's Note:**

> I made this for the Catgirl Mari Discord server. You're welcome, and I'm not sorry. Primarily because I like seeing people's reactions.  
> PSA: Don't fuck cats. Or dogs. Or any other nonhuman animal, for that matter.


End file.
